another_jim wrote:This is a quick interim report on temperature management, I still have a ton of data to crunch before I make a more complete entry in the bench review.
There are some oddities. The thermosyphon group runs about 10C lower than the brew boiler temperature. If you make a shot without a prior flush, the temperature will rise from the group temperature by about 3 degrees C. A 10 second heating flush (paddle full open) will get you a steady temperature about 4C below the brew boiler temperature. A 5 sec flush will get you a temperature about 6C below the brew boiler.
This is a fairly extreme version of double boiler "cold nose." The upside is that you can change temperatures on the fly, by changing the timing of the heating flush (the automatic shot timer makes this easy) The downside is that super precise temperature control will require a flush and wait routine. Dan and I will post the details for this as soon as we've got it figured out.
Not sure what's going on with your machine, the UK machine I tested was not like that at all. I also assume you are not talking about the normal 10C offset, but the displayed temp on the PID after the offset is accounted for?